Such a method is already known in the art, e.g. from the article "A B.sub.-- ISDN Local Distribution System based on a Passive Optical Network" by J. W. Ballance et al, Globecom '90, San Diego section 3.3, 2nd paragraph.
In this known method which is applied in a transmission system wherein an exchange end or main station is connected to a plurality of customer ends or substations via the cascade connection of a common optical fiber link and respective individual links, the equalisation delay also called delay compensation of a customer end is determined in the following way. The customer end is told by the exchange end to transmit a reply signal to the latter without delay compensation, whilst at the exchange end first the propagation delay of the customer end is measured and afterwards the delay compensation is determined by substracting this delay from the maximum propagation delay of the system.
A drawback of this method is that to avoid interference of the above mentioned reply signal with information signals transmitted by other customer ends over the common link, the latter ends have to stop transmission of information signals during a time interval at least equal to the maximum propagation delay of the system. In the mentioned article this delay is equal to the time equivalent of 71 asynchronous transfer mode cells which in fact gives only a minor reduction in the network throughput, but might result in an unacceptable jitter due to cell accumulation.